Relay arrangement for changing the tuning of wireless apparatus



M rch 3o, 1926.

c. scHwARz RELAY ARRANGEMENT r-oR CHANGING THE TUNING o1 WIRELESS APPARATUS Filed oct. 51 1921 y Receiver #ook (am S i JANE/WOR ,jy-WW A TTORNE YS Patented Mar. 30, 1926.

UNITED STATES CARL SCHWARZ, OF CHARLOTTENBURG,

NEAR BERLIN, GERMANY, AssIGNoR 'ro WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

RELAYARRANGEMENT FOR CHANGING THE TUNING F WIRELESS APPARATUS.

Application led October 31,-1921. Scria1` No. 511,828. -i I To all whom t may concern:

Be it known thatYI, CARL SCHWARZ, residing at Charlottenburg, near Berlin, Germany, have invented certain Anew and useful 5 Improvements in Relay Arrangements for Changing the Tuning of Wireless Apparatus, of which the following is a specification. This invention relates to radio signaling apparatus of the type shown in my corpending applications Ser. No. 511,832, filed Oct.v 31, 1921, and Ser. No. 511,827, filed Oct. 31, 1921. Radio signaling apparatus of this type has provision for changing the wave length by the operation of a switching device.

It is an object of the present invention to provide for changing the tuning of the signal-sending device without changing the tuning of the `sending antenna so that the sendingk system will thereby be prevented from radiating signals.

Other objects of the invent-ion and specific details of the construction will be apparent.

from the following description and the accompanying drawing, in which- The single figure is a diagram showing thedapparatus and system of connections use The sending device includes an antenna system Ts. This may be any usual form ofy sending antenna, such as an antenna and a ground connection. The antenna circuit includes a coil Ls which is connected to a switch regulated by the relay Rs. In the illustrated position of this switch, the whole r of the coil Ls is included in the antenna circuit. When the relay Rs moves the switch to the opposite position, a portion. only of the coil Ls is thus included. The sending apparatus S associated with the antenna system Ts includes a vacuum-tube oscillation generator Vs. Associated with this generator is an oscillating circuit including a coil Lg which is controlled by the relay Rg. In the illustrated position. .the whole of the coil *5 Lg is included in the oscillating circuit. In the op 'osite position of the relay, a portion only o Ithis coil is thus included.

The receiving instrument E is connected to the antennaeaTe which may be any form of antenna'systennas explained in connection with the sending device. The receiving instrument includes a vacuum tube Vc-v and isl cou led vto the'antennagjcircuit A condenser le is connected in parallel to a l,

coil in the antenna circuit, and the 'condensery Kk is similarly connected in an oscillating circuit. These condensers are thus connected when the switch controlled by the relay Re is in the illustrated position. In the opposite position of the switch, a condenser Cg is connected in the antenna circuit in the- -rectly atune itself to the station with which it is to communicate. The relays Rg, Rs and Re are controlled by a common circuit which is opened and nclosed by the switch u. Thisswitch may be actuated by the selective station-calling device or by the switch hook, whichv is moved when the receiver is lifted. As explained in the above mentioned copending application- Ser. No.` 511,827 one or the other way of controlling the switch Will be used according as the change in tuning is to be made at the calling or the called station.y

It is sometimes desirable, for adapting the illustrated station to particular crcum: stances, to tune it to receive signals s ent out by some other station and, at the same time, render its sending .device inoperative, in order that there shall be no danger of the operator at the illustrated station interferingy with the signals while listening to a distant station. This is accomplished by means of the extra switch .a which may be a telegraph key or any other desired form of manually operated switch: l/Vith the apparatus in the illustrated position, that is7 with the switch u open, if the key a is moved, the relay Rg will be energized, while the relays Rs and Re remain decnergized. This will result in tuning the oscillating circuit in the sending system to a different wave length from the radiating system of the sending device. Consequently,l the oscillations generated will not be sent out andthe station cannot, therefore, interfere with the signals coming from the distant station. This is parfrom the radiating circuit in that device and,

consequently, no signals will be sent and the action of the sending device at the illustrated station Will produce no noises in the telephone.

Many variations in the details of construction Will occur to those skilled in the art and many dil'erent situations in lwhich this in vention can be used, Without de arting from I, therefore, do not intend to limit it except the spirit thereof, Will at once e apparent,

as necessitated by the prior art or indicated in the claims.

I claim as my invention:

1. In a radio signaling system, means for changing the tuning, relays for controlling said means and a device for controlling one of said relays independently of the others.

2. In a radio signaling system, a sending device and a receiving device, lmeans for controlling the tuning of each of said devices, relays for actuating said means'and means 'for operating one of said relays independcausing one of said relays to operate independently of the others.

4. In a radio sending system, a radiating circuit, an oscillating circuit, switching means for changing the tuning of each of said circuits, a pair of relays for operating said switching means, and a device for operating the relay associated with the oscillating circuit independently of the other relay whereby the tuning ot the oscillating circuit and the radiating circuit may be made to`differ from each other when desired.

In testimony whereof I aiiix my signature.

CARL SCHWARZ. 

